Carreau fluid
Carreau fluid is a type of generalized Newtonian fluid where viscosity,, depends upon the shear rate,, by the following equation:
Where:,, and are material coefficients.
= viscosity at zero shear rate
= viscosity at infinite shear rate
= relaxation time
= power index
At low shear rate a Carreau fluid behaves as a Newtonian fluid with viscosity. At intermediate shear rates, a Carreau fluid behaves as a Power-law fluid. At high shear rate, which depends on the power index and the infinite shear-rate viscosity, a Carreau fluid behaves as a Newtonian fluid again with viscosity.
The model was first proposed by Pierre Carreau.